This proposal requests support only for the analysis of data collected during the past three years in an NIH-sponsored study. This study has four major objectives: (1) to determine the prevalence of peripheral arterial disease (PAD) in a defined population by non-invasive techniques; (2) to investigate the etiology of PAD by evaluating the association of certain cardiovascular disease risk factors with PAD; (3) to evaluate the degree of association between PAD and coronary heart disease (CHD) on a population basis in order to determine whether non-invasive tests of PAD can be utilized as a marker for CHD; (4) to determine the status of the microvasculature in these subjects using non-invasive conjunctival photographs and to compare these microvasculature results with risk factors and the PAD testing results. Half of the study group represent a random sample of a defined community and half were selected for hyperlipidemia. Information on multiple risk variables was collected. These variables include diet, medications, alcohol use, cigarette smoking, past medical and surgical history, history of vasectomy, height and weight, blood pressure, arcus senilis, cholesterol, triglycerides, HDL, LDL, and VLDL cholesterol, cholesterol/triglyceride ratio in VLDL, apoprotein E and its subfractions, fasting plasma glucose, glycosylated hemoglobin, and IgE. The dependent variable, PAD, was measured by four non-invasive tests: segmental blood pressure, flow velocity by Doppler ultrasound, post-occlusive reactive hyperemia, and pulse reappearance time. For the third objective, the PAD-CHC association, PAD measurements will be used as the independent variable and cardiac morbidity and/or mortality will become the dependent variable. Cardiac morbidity data, including exercise EKG, are currently available and detailed validated mortality information is available without cost from a continuing Lipid Research Clinic follow-up study. The fourth objective will be addressed by computer analysis of image enhanced photographic negatives of the conjunctival microvasculature and comparing results with PAD results.